The electro-pneumatic gun

With his electro-pneumatic gun, Volta demonstrated the electrical ignition of flammable gases, anticipating remote signal transmission and modern engine ignition systems.

Flammable air and sparks

In January 1777, after igniting flammable air with a spark produced by a flint, Volta conceived the idea of an experimental weapon loaded not with gunpowder, but with a mixture of flammable air and deflogisticated air. Ignition occurs as in a traditional arquebus, but through an entirely new principle.

Electric ignition

The project improves further when Volta discovers that the explosive mixture can be ignited directly by an electric spark generated inside the container. This led to the creation of the electro-pneumatic gun, capable of transforming electrical energy into a controlled explosion.

Volta’s gun and electrophorus (Tempio Voltiano, Como)
Pistola di Volta ed elettroforo

An object of wonder

The first pistols were made of wood, while later ones were made of glass or metal and took on different shapes. The invention aroused great curiosity in scientific circles and became a spectacular tool for demonstrating the power of electric sparks applied to flammable gases.

Remote electricity

Volta also experiments with firing the gun remotely, transporting electricity through conductive wires. These experiments reveal an early intuition of remote signal transmission, a true anticipation of the principle of the electric telegraph.

Project for the ignition, controlled in Como, of a gun located in Milan, by means of an electric discharge conducted through a metal wire, supported by insulating poles and a water channel (Volta’s autograph, Cart. Volt. E1, Lombard Institute). 113b.bmp Volta’s pistol (Voltiano Museum, Como)
Progetto dell’accensione, comandata a Como, di una pistola posta a Milano, mediante una scarica elettrica condotta per un filo metallico, sostenuto da pali isolanti e per un canale d’acqua

Applications and demonstrations

Volta hypothesises further uses for the gun, such as a “storm warning device”, and even describes a flammable air bomb. In famous public demonstrations, he shows the violent detonation produced by a mixture of air and flammable gases ignited by an electric spark in a closed container.

Autograph drawing by Volta, describing the device known as the ‘storm warning device’ (Cart. volt., Istituto Lombardo)
Disegno autografo di Volta, che descrive il dispositivo cosiddetto avvisatore di temporali

A modern insight

As the first person to achieve the combustion of gas mixtures in closed vessels using an electric spark, Volta can be considered a precursor to the ignition systems of modern gasoline engines. Once again, his experimentation anticipated future technological applications.